The present invention relates to a press for compacting or compressing elongated radioactive structural elements, such as fuel cell skeletons, including a horizontally disposed press line that comprises a press shaft provided with a cover, a press ram operated via a hydraulic cylinder, and a removable counterpunch in place of which, after a compressing process has been completed, is inserted a transfer shaft into which is introduced the highly compressed pressed object via further advancement of the press ram. The present invention also relates to a method for operating such a press.
A press of this general type was disclosed in German Offenlegungsschrift 38 02 966. The press ram thereof is driven by a long hydraulic cylinder. Via the press ram, a fuel cell or element skeleton is compressed in the longitudinal direction against the base of the press shaft. After the compression, the pressed object is pushed into a transfer shaft with which it is conveyed out of the press. The transfer shaft extends about the pressed object, so that broken pieces of skeleton remain secured, and an expansion of the volume in the radial direction due to expansion of the pressed object is prevented. The ability to keep the pressed object within certain dimensions is advantageous for further operating stages.
Due to the necessary long hydraulic cylinder, a drawback of this proven press is its great structural length, which also makes a remote handling more difficult. It was furthermore discovered that toward the end of the compressing process, smaller particles can escape from the press line out of the gaps that necessarily result between the end face of the press body and the end face of the counterpunch during assembly. Due to the resilience of the pressed object after conclusion of the compression process, the pressed object can swell in the axial direction and thereby prevent removal of the counterpunch.
German Offenlegungsschrift 34 44 570 proposes an apparatus with which elongated radioactive parts that have the same geometry are cut into pieces and are subsequently introduced into a receptacle. The length of these pieces corresponds approximately to the height of the receptacle.
By means of a packing mechanism, pieces that are already in the receptacle are pressed to the side in order to provide space for further pieces. This mechanism is designed for pieces having a very specific geometry; it is not suitable for compacting or compressing elongated radioactive parts having varying geometries, such as non cut-up fuel cell skeletons.
German Offenlegungsschrift 33 00 359 furthermore proposes an ejection mechanism for compactable material, where the material, which is in pieces or is granular, is compressed into plugs in a compression chamber. In so doing, the degree of compression can be set by changing the counter holding force of the closure means for the compression chamber. The use of this ejection mechanism is limited to loose material that can be poured.
It is therefore an object of the present invention to provide a press of the aforementioned general type that has a shorter overall length, that to a large part can be handled or controlled remotely, and that during the compression process as well as during introduction of the pressed object into the transfer shaft, prevents any particles from escaping out of the press line, with this press nonetheless assuring that the unavoidable swelling of the pressed object in the axial direction will have no impact upon the removal of the counterpunch or the insertion of the transfer shaft.